The present invention concerns, as new industrial products, the derivatives of .alpha.-D-xylose defined by formula I below. It also concerns the process for the preparation of these compounds, as well as the therapeutic compositions containing them as active ingredients.
Derivatives of .beta.-D-xyose, in particular derivatives of benzoyl- or .alpha.-hydroxy-benzyl-phenyl .beta.-xylosides, recommended in therapeutics for the treatment of venous thromboses, are already known, for example, according to EP-A0051023.
Derivatives of benzyl-phenyl .beta.-D-xylosides, exhibiting a hypocholesterolemiant and/or hypolipidemiant activity, are also known according to EP-A-0133103.
Derivatives of the type .beta.-D-phenylthioxylosides, used for their antithrombotic activity, are also known according to EP-A0365397, EP-A-0290321, EP-A-0133103 and EP-A-0051023.
The antithrombotic activity of a certain number of derivatives of .beta.-xylose has also been reported and studied in the article of J. Med. Chem, 1993, 36, (no. 7) pages 898903. Research carried out in the laboratory has shown that these derivatives of .beta.-D-xylose are good substrates of galactosyl transferase I. For this reason, these compounds, active when taken orally, initiate the synthesis of glycosaminoglycanes (GAGs). After administration of the compounds orally, the circulation rates of GAGs are appreciably increased and approximately 20% of the latter display an activity of the dermatan-sulphate type capable of inhibiting thrombin, via HC II (Heparin Cofactor II), this initiation of the biosynthesis of GAGs probably being responsible for the antithrombotic activity observed experimentally for the compounds mentioned previously. In correlation with the potential of these compounds to reduce the formation of venous thromboses, only the .beta. configuration derivatives of D-xylose increase the synthesis of GAGs. The other derivatives of the glycopyranoside type have proved to be inactive in this area, both from the biological standpoint on the synthesis of GAGs, as well as from the pharmacological standpoint on the reduction or prevention of venous thromboses.
The activity of certain derivatives of .beta.-D-xylose, in particular estradiol .beta.-D-xyloside, has been studied in the publication Journal of Biological Chemistry, 1991, 266, (No. 11) pages 6674-6677 and the authors establish a relationship between this compound and the biosynthesis of heparane sulphate, as well as an inflator role of .beta.-D-xyloside in the synthesis of chondroitin sulphate. These studies confirm the benefit of derivatives of .beta.-D-xylose for the treatment or the prevention of venous thromboses.
According to the invention, it is proposed to provide a new technical solution making it possible to arrive at new products that are biologically beneficial with respect to arterial atheromatous platelets.